Building construction



Aug. 11, 1936. f A. F. BEMIS 2,050,256

I BUILDING CONSTRUCTION Filed April 25, 1935 e Sheets-Sheet 1.

I //e/ f fie s' 2 4%, W

Augfll, 1936. A. F. 'BEMIS 2,050,256

BUILDING CONSTRUCTION Filed April 25, 1955 6 Sheets-Sheet 2 In verztm;

AZZert Aug. 11, 1935. A. F. BEMIS BUILDING CONSTRUCTION Filed April 25,1953 6 Sheets-Sheet 3 Inventor," r F5 A. F. BEMIS BUILDING CONSTRUCTIONFiled April 25, 1935 6 Sheets-Sheet 4 M5 ma 1 m4 m0 //2 /00 //2 q 2 K1 1f I mg J72 verzzar,"

. Au .11,1936. A BEMIS 4 2,050,256

BUILDING CONSTRUCTION Filed April 25, 1935 6 Sheets-Sheet, 5 i y- 15.13.274 704 9 30 "/a I M6 /dZ m Aug. 11, 1936. A. F. BEMIS 2,050,256

BUILDING CONSTRUCTION H Filed April 25, 1953 6 Sheets-Shqet 6 frzveizlm;

AZ rziYBe 5%W v Y Any this purpose.

Patented Aug. 11, 1936 UNHTED STATES PATENT OFFIQE BUILDING CONSTRUCTIONAlbert F. Bemis, Newton, Mass,

assignor to Application April 25, 1933, Serial No. 667,846

13 Claims.

This invention relates to an improved method of forming walls ofcementitious material and to walls which are produced as a result of themethod as well as to form elements employed for Heretofore it has been.customary in the erection of walls of cementitious material, such asconcrete walls, to assemble forms including temporary boarding andsuitable uprights to support the boarding and then to pour cement intothe forms. The erection of the temporary forms and the stripping of thesame from the set cement has been troublesome and relatively expensive.The present invention avoids these features of concrete construction andemploys sheet material properly supported to act as a form for thepoured concrete or the like.

In some respects the present invention comprises a further deevlopmentof and improvement upon the method and construction disclosed in mycopending application Serial No'. 648,407, filed December 22, 1932.Further developments of this invention are also disclosed in mycopending applications Serial Nos. 735,809 and 735,810, filed July 18,1934. The present invention may be employed in various environments butis particularly suitable for the erection of concrete foundations orcellar walls upon a suitable footing, a framework first being erected tosupport the sheet material which acts as the actual form. Thus, forexample, in the case of a house being constructed with a metal frame,the main corner posts, i. e., posts at the intersections of the walls,may first be erected on the footing and connected by suitable sillmembers which are employed to support the sheet material comprising theconcrete form. In practice I prefer first to support a sheet elementtoprovide a form about each of these corner posts and then topourcementitious material into this form, thus in effect afiording a metalreinforced concrete post at each wall intersection. Thereupon the sheetmaterial for the wall portions extending between the posts may beconnected to the envelopes surrounding the concrete of the latter and tothe sills extending between the posts.

In the case of other walls, as for example in buildings being erectedwith a conventional wooden framework, sills may first 'be disposed ontemporary posts of adjustable height, and the concrete may be pouredinto envelopes of sheet material or fabric between these posts, thus toprovide supporting means to hold the sills in place when the temporaryposts are removed. Thereafter the spaces previously occupied by theposts may similarly receive form elements of sheet material into whichconcrete is then poured. In certain cases the temporary posts may remainplace and be embedded in the poured concrete, if desired.

One aspect of the invention relates to the provision of sheet materialin suitable arrangements to provide forms for relatively long concretewalls with posts at their ends, the sheet material being arranged withnumerous web portions extending between opposite face portions that areto define the faces of the wall, thus providing means for holding theface portions in position and preventing undue bulging under thehydrostatic pressure of the poured cementitious material. Thus inpractice the sheet material may be formed into a. plurality of cell-likechambers with a vertical extent substantially corresponding to theheight of the wall to be poured, and each having a triangular crosssection. In other developments of the invention the sheet material maybe similarly formed into cells or chambers of square or rectangularcross section. While a variety of sheet materials may be employed forthis purpose, I prefer burlap or similar coarse fabric due to its lowcost and high strength.

Further features of the invention relate to the provision of temporaryfastening means, brackets, and the like for connection of the sheetelements to the supporting framework, such as studs, sills, and floorjoists; the latter in certain cases may be secured to the sills beforethe wall is erected.

In the accompanying drawings:

Fig. 1 is a view partly in section and partly in elevation of a cornerportion of a typical metal framework to which my improved formarrangement may be applied;

Fig. 2 is a horizontal section of such a corner portion with the formsapplied thereto;

Fig. 3 is a vertical section of a sill or first floor girt with a formconnected thereto;

Fig. 4 is a vertical section of the bottom of a frame and the adjoiningfooting showing a form associated therewith;

Fig. 5 is a vertical section showing the application of a formarrangement to a wooden framework;

Fig. 6 is a sectional view on line 6--6 of Fig. 5;

Fig. '7 is a diagrammatic top view of a typical unit which may beassembled with similar units to afford a form;

Fig. 8 is a diagrammatic top view of such an assembly of units;

Figs. 9 and 10 are top views corresponding to Figs. '7 and 8, butshowing optional forms of units;

Fig. 11 is a view similar to Figs. 7 and 9 but showing an optional formof burlap unit;

Fig. 12 is a diagrammatic view of a corner assembly including units ofthe type illustrated in Fig. 11;

Fig. 13 is a similar view showing the unit of Fig. 11 combined withunits of the type illustrated in Fig. '7;

Figs. 14 and 15 are horizontal sectional views of wall assembliesshowing the posts of poured cement with sheet form units connectedthereto ready for the reception of cementitious material;

Fig. 16 is a top plan view of a corner arrangement showing the manner inwhich the corner of a floor frame may be temporarily supported to holdsheet form members in place; and

Fig. 17 is a horizontal section of a typical wall constructed inaccordance with this invention.

Referring first to Fig. 1 of the accompanying drawings, the numeral Idesignates a suitable footing of concrete which may be formed in theconventional manner. Mounted upon this footing are the corner posts orposts at the intersections of exterior and interior walls or betweenexterior walls. One of the latter is designated by the numeral 2 and isconnected to the first floor girts 3, which may comprise horizontal webplates with pairs of angles secured to the outer margins of the upperand lower faces of these plates, suitable reinforcing brackets 4connecting the ends of the sills to the lower post 2 and the post 2*,which is disposed thereabove for the first story of the building. Uponthe footing, sills 3 in the form of channels may be connected to thelower ends of the uprights 2 by brackets 4. The framework just describedis merely selected by way of example of any typical framework whereinthe main posts may extend downwardly to the footing. A concrete wall maybe erected between the sills 3 and the footing I by the employment ofsuitable fabric form units in combination to define a wall form.

Now referring to Figs. '7 and 8, it may be seen that a sheet of fabricsuch as burlap may be provided to define a substantially equilateraltriangle having a sheet portion I to define a portion of the outer faceof a wall, and having similar sheet portions H to comprise tensionelements. One of the elements H may be extended to provide an outer facesheet portion if), i. e. to cooperate With the adjoining portion H ofthis unit and one of the portions ll of a similar section in defininganother chamber or cell of triangular cross section. Between the facesheet portion IO and the tension portions i i of the unit, the fabricmay be folded upon itself and stitched, as indicated, to provideoutstanding ribs l2. Similarly where the elements H meet each other anda face sheet portion l the fabric connecting portion IE! with theadjoining integral section i l is folded back on itself in the form of arib 15 to receive the free edge of the other tension element or sectionI I, which is secured thereto by stitching i3. Sheet units of this typemay be secured to each other in the manner illustrated in Fig. 8 toafford a form assembly of any desired length. For this purpose the freeedge IE! of one unit is secured by stitching M to the adjoining rib i ofthe next unit, while the juxtaposed ribs I2 of the units at the oppositeface of the assembly are secured together by stitching l6.

Figs. 9 and 10 illustrate different sheet units which may be combined toafford an assembly of the same general shape as illustrated in Fig. 8.Such units may comprise sheets of fabric folded to provide divergingportions 29 of similar size at an angle of substantially 60 to eachother, these portions being connected by a flange 25 formed by foldingthe fabric back on itself, the flange portion 2! of each unit beingconnected to the free edges of elements of two adjoining units, saidelements extending at 60 to each other and 60 to the adjoining wall ofthe first unit. Thus an assembly is again provided having a plurality ofcells of triangular cross section.

Sheet assemblies of the type illustrated in either Figs. 8 or 10 may besupported from the girts 3 of a frame such as illustrated in Fig. 1 tocomprise forms for the pouring of cementitious material. In many casesit is desirable to provide a relatively thick wall and for this purposeI may arrange two of the assemblies of the general type illustrated inFigs. 8 and 10, with their face sheets in juxtaposition to provide awall of double thickness. Fig. 2 illustrates such an arrangement, thefabric forming the triangular cells in this illustration of theinvention being arranged, however, in a slightly different manner, whichwill be described.

It is advantageous in employing such a. method of wall erection flrst toform concrete posts at the corners of Walls or at wall intersections byemploying suitable fabric envelopes and to connect the fabric forms ofthe straight wall portions with these envelopes. My copendingapplication Serial No. 648,407, filed December 22, 1932, discloses moreparticularly the manner in which such posts may be formed about an innermetal reinforcement. Thus, referring to Fig. 2, the post 2 may beprovided with an inner portion of substantially square cross section andwith outstanding flanges or ribs which may support vertically spacedclips 3! receiving inturned flanges 32 upon semi-circular hoop elements33. A burlap envelope 34 of substantially cylindrical form may be formedby stitching two burlap sheets together, the margins of the sheetsadjoining the lines of stitching being disposed between the inturnedflanges of the hoop elements 33, as shown in Fig. 2. I'his envelope thenreceives poured cementitious material which distends the envelope sothat it occupies a substantially cylindrical space. After the envelopehas thus been distended in this manner, and preferably after thecementitious material therein has been allowed at least initially toset, the fabric forms may be suspended from the sills 3 between theposts. These forms may be connected to the sills 3 in any suitablemanner, for example, by brackets 2| (Fig. 3) having pins 22 passingthrough openings in their outer portions and preferably extendingthrough hems disposed along the upper edges of the outer face sheets ofthe form. If it is desired to erect a wall of double thickness, as isoften the case, the adjoining face sheets of the form assemblies may beconnected by twisted wire tires 35 to the web plates of the sills 3,suitable openings 36 being provided in these plates to facilitate such aconnection. The lower end of the form may be connected to the footing inany suitable manner; for example, the outer face sheets may haveoutturned flanges or extensions 31 (Fig. 4) secured by nails, angles orthe like to the footing. As shown in Figs. 2 and 4, angles 45 may beprovided with horizontal flanges having slots or openings 46 to receivehold-down screws 41.

The lower ends of the inner face sheet portions 48 of the sheet unitsmay be connected by Wire clips or hooks 39 to the sill 3 suitableopenings 36 being provided in the bight portion of this member toreceive the members 39.

Fig. 2 illustrates triangular assemblies of the same general characteras shown in Figs. 8 and 10 but which are formed in a slightly differentmanner from a continuous sheet of burlap or the like. Thus the burlapmay be first folded back upon itself to provide an inner face section ofone of the form assemblies, as designated by .numeral 46, then may beextended in a single thickness or tension element 4| to an opposite faceportion, designated by the numeral and may then be extended inwardly toafford another tension portion 4!, of a second inner facesection definedby succeeding portions folded back upon themselves and designated by thenumeral 49.

Thus Fig. 2 illustrates an arrangement wherein a continuous sheet whichhas a width at least equal to the height of the wall which is to beerected may be folded back upon itself to provide a form with facesheets of double thick.- ness and diagonal tension sections of singlethickness therebetween. Obviously the portions of this assembly aresecured to each other by stitching at the corners of the triangularcells thus provided.

Any suitable arrangement may be employed for arranging fabric betweenthe ends of the wall assembly and the cylindrical envelope 34 of thepost. Thus, as shown in Fig. 2, the fabric units 5& may have theirintermediate portions extending transversely of the end of the wall formand may have their ends comprising portions doubled back to provide aflange of double thickness in the plane of the wall face, designated bynumeral 5|, the outer end of each flange being connected to the end ofthe wall sheet portion of the main wall assembly. The inner ends ofthese flanges upon the outer faces of the wall may be connected to afabric sheet extending from the outer face of one of the units 55 to theouter face of the other and curved about the outer surface of theenvelope 34 of the post. At the inside of the corner, the units may beconnected to each other adjoining the junctures of their body portionsand flanges 5| by means of stitching 52. Thus spaces to be poured areprovided between the post and the main wall forms. As previouslyexplained, the sills are provided with suitable openings 35 which permitthe pouring of cement into the triangular spaces of the fabric assembly,while in the case of a wall of double thickness the cement may be pouredat either side of the sills. The arrangement of the tension elementssuch as elements 4! permits the face sheets strongly to resist bulgingso that there is only a slight localized bulging between adjoining seamsor ribs at the outer face of the wall. The arrangement of two sets ofunits such as shown in Fig. 2 affords a relatively strong reinforcingweb in the center of the poured wall. The burlap employed for thispurpose preferably has a sufiiciently coarse mesh, so that it "mits theintrusion of the poured cement to some extent between its strands, thusaffording numerous integral bridges or connections between concretebodies po-ured at opposite sides of a tension sheet section 4! andaffording an interlocking of the concrete with the burlap face sheets.When face sheets of double thickness are provided, as shown at Fig. 2,adequate fabric is provided to receive a coating of waterproofingmaterial such as an asphalt or tar composition.

When sheet form assemblies of the general type already described are tobe employed for erecting a form without metal reinforcements or postsextending upwardly from the footing, temporary uprights may be employedfor supporting frame members or sills from which the form assemblies aresuspended. Figs. 5 and 6 are illustrativeof such an arrangement. Sills10 are arranged adjoining the top of the wall to be formed and may havetheir ends connected to each other in the conventional manner. Thesesills are supported at the corners of the floor frame, thus provided bytemporary uprights H which may comprise telescoping tubular memberswhich are adjustably clamped in place by set screws 12 to afford thedesired height for the upright. These temporary uprights may be'providedwith annular flanges at their upper and lower ends which may be securedto the footing I and to the sills TO by removable fastening means suchas nails, screws or the like. Floor joists 15 may be secured to thesills ill in the usual manner before the concrete walls are formedbeneath these sills.

Sheet form assemblies of the general character illustrated in Figs. 8and 10 may then be fastened to the wooden floor framework which isafforded by the sills l6 and joists 15. For this purpose the outer facesof the sheet form assemblies may have upwardly extending portionsdesignated by numeral 1'! which are secured against spacer strips orboards 19 by retaining strips 18, suitable nails 89 preferably beingdriven through the strips 18, extensions I7 and spacers 19 to securethese parts to the sills Ill. The inner face of a form assembly whichextends transversely of floor joists 15 (Fig. 5) may be provided with anend portion .86 turned over to lie in a substantially horizontal plane,which is held in place by a retaining strip 8! that is secured by nails88 to the lower portions of the floor joists. The inner face portions ofthe form assemblies'may be secured to joists 15 which are parallel toand adjoining a sill 10 (Fig. 6) by means of a retaining strip 33secured in place by nails 84 which are driven through the strip 83 andan upwardly extending continuation of the inner face of the sheet formassembly as well as into the joists 15. This arrangement permits theprovision of forms disposed between the temporary uprights ll. The innerfaces of these forms are adequately spaced from the adjoining sills 10to afford suitable openings for the pouring of cementitious material.When concrete or the like has thus been poured into the spaces affordedby the forms, it is allowed to set to afford supporting means upon whichthe sills 10 may rest. Thereupon the set screws 12 of the temporaryupright H may be released so that the uprights may be removed from theirpositions in engagement with the lower faces of the sills. Suitablesheet forms of sheet material may then be supported in the spacespreviously occupied by the temporary uprights and these forms may thenbe filled with cementitious material filling the spaces between theconcrete walls beneath the sills.

If desired, the temporary uprights ll, rather than being located at thecorners of the framework, may be located under the sills adjoining butspaced from the corners, and temporary forms may be arranged so as topermit the pouring of the corner posts, after which the temporaryuprights may be removed and the straight wall forms suspended from thesills and poured.

Figs. 11 and 12' illustrate a sheet form unit which may comprise panelportions I00, I and iii-2 enclosing three sides of a square, as viewedin horizontal section, flanges Hi4 being provided by folding the fabricbetween the sections I00 and NH, and sections llll and I62 respectively.Similarly the outer edges of sections I09 and H32 may be folded toprovide flanges M6. Units of this type may be connected to each other bystitching H2, as shown in Fig. 12, to define a straight wall sectionwith the panels lOl forming tension members and the panels I and H12defining the opposite faces of the wall to be poured. Such a unit maydefine a square corner post by the application of a filler panel 109connected to the outer edges of sections I00 and I02, as illustrated inFig. 12; this same arrangement may be employed at the corners betweenthe ends of wall assemblies of the type illustrated in Figs. 5 and 6. Aunit of this character may also be combined with a unit made up of aplurality of triangular elements, such as are shown in Fig. '7. ThusFig. 13 illustrates the arrangement of triangular elements with theirsides It), H and I0 defining straight wall sections and with one of theunits illustrated in Fig. 11 disposed at wall intersections.

Fig. 16 illustrates a typical arrangement which may be employed whenpermanent posts are not to be embedded in the concrete wall. For thispurpose blocksST may be disposed upon the ground adjoining theexcavation for the footing, and a diagonal member 93 may extend betweenthe uprights and be arranged to support the ends of sills Til which areconnected to each other in the conventional manner. The diagonal member93 may cooperate with the outer edges of the sills m in receiving theinturned upper marginal portions of the portion of a burlap formdefining a substantially square post, for example, a form of the generalcharacter illustrated in Fig. 13, inturned margins of the burlap beingsecured, for example, to the wooden members by nails or brads 96. Theouter face of the elongated form assembly may be secured to the outerface of each of the sill elements, while the end of its inner face maybe connected to the diagonal member 93 as well as to the fabric envelopefor the corner post. With this form of the invention the post is firstpoured and the concrete allowed initially to set so that the ends of thesills are supported on concrete corner posts. Thereupon the uprights ai, blocks 9'! and diagonal member 93 may be removed and the fabric formsfor the straight sections of the wall may be arranged in any suitablemanner; for example, they may be supported in the general mannerillustrated in Figs. 5 and 6.

Figs. 5 and 6 also illustrate the provision of ties w which may beemployed with fabric form assemblies of the type illustrated herein.These tie members may be extended between opposite face sheet portionsof the assemblies being provided with heads Ill! upon the outer faces ofthese face sheets and, as illustrated, the intermediate portions ofthese ties may conveniently extend through small openings in the tensionsections of the' form assemblies. The ties 180 preferably may be of thewell known type employed in mattress making.

Fig. 14 illustrates a typical wall assembly made up in the generalmanner which is diagrammatically illustrated in Figs. '7 and 8 andprovided with ties m At the corner provided by intersecting walls ofthis type, a slightly different type of fabric form may be employed todefine a substantially circular corner post assembly. This fabric may besuspended from the sill elements in the manner illustrated in Fig. 16and may comprise an outer sheet portion I I0 and an inner sheet portionIII which are connected to each other. The central portion of the sheetH9 extends between the outer face sheet portions of the wall assemblieswhile the end portions thereof engage the end tension elements of thewall assemblies, the inner edges of the sheet HE] being connected by thenarrow strip III. A space which may be substantially circular in crosssection may thus be provided for the initial pouring of concrete topermit first the erection of a concrete post at the corner afforded bythe intersection of straight wall portions. After the post-has thus beenpoured in this manner, the straight wall form assemblies may beconnected to the envelope surrounding the concrete of the post. Thus, asshown, tension elements It at the end of these sections may be wrappedabout curved surface portions of the sheets H0 and secured thereto.

Fig. illustrates another form of wall assembly wherein two similar sheetmembers I have their inner edges connected to the ends of the inner facesheets of the straight wall portions as well as to the inner ends of theend tension elements of these portions. The outer edges of the. sheetslZB are connected to the ends of the outer face sheets of the straightwall portions and also to the edges of a relatively narrow bridgingstrip E25. Thus, the members I20 and l2l may define a substantiallycylindrical space which may be filled with cementitious material in themanner already described.

It is evident that post assemblies of the type illustrated in Figs. 14and 15 may be employed at the corner of a floor frame which is supportedintermediate its corners by temporary uprights 'H or the like.

Fig. 1''! illustrates a cross section of a typical wall formed inaccordance with this invention, the face sheet portions of the assemblybeing slightly distended by the pressure of the poured concrete so thatthe wall may have a typical face of undulatory form rather than beingsubstantially planar as is the case with a conventional concrete wallerected by the use of form boards.

It is evident that this invention affords elements permitting theemployment of inexpensive and quickly erected forms of sheet materialand that these forms may be readily manufactured from inexpensive andrelatively strong fabric such as burlap. The invention permits the majorportion of the work in making forms to be performed in a manufacturingestablishment and requires the minimum of work in erecting the forms insitu. Thus, the forms may be prepared in advance and quickly connectedto the framework, being suspended from temporary uprights or the like asconditions may require so that actual pouring of cement to provide acellar wall or the like may be initiated in a very short time after thefooting has been properly prepared.

After the concrete walls have been poured in this manner and have beenallowed to set for a suitable period, the burlap may receive a suitablecoating of waterproofing material such as an asphaltic composition, ifdesired. This coating also serves to afford a protection for the burlapitself. This invention avoids the necessity of stripping forms andpermits succeeding operations in the erection of the building as, forexample, the erection of framework for successive stories, the laying offloor boards or the like to proceed without interference by laborerscarrying on the form stripping operation. Thus, econom and facility inbuilding construction is afforded by the employment of sheet elements ofthe character illustrated herewith.

I claim:

1. Method of building a concrete wall on a suitable base, comprisingerecting a pair of spaced uprights upon the base, mounting a supportupon the uprights to span the distance therebetween, arranging envelopesof flexible sheet material about said uprights, filling and distendingthe envelopes with cementitious material, permitting the cementitiousmaterial initially to set, suspending a form of flexible sheet materialfrom the support between said envelopes, and pouring cementitiousmaterial into said form to fill the space between said distendedenvelopes.

2-. Method of building a concrete wall on a suitable base, comprisingerecting a plurality of spaced temporary uprights, mounting supportsupon the tops of the uprights to span the distances between uprights,suspending forms of flexible sheet material from the supports andbetween uprights, filling and distending said forms with cementitiousmaterial, permitting the same to set, removing the uprights, suspendingenvelopes of sheet material in the spaces which were occupied by theuprights, and filling said envelopes with cementitious material.

3. A form for a concrete wall comprising a sheet of textile fabricfolded back and forth upon itself to provide opposite face sections ofdouble thickness and intermediate connecting portions of a singlethickness, said sections cooperating toafford cells or chambers ofsubstantially triangular cross section.

4. A form for a concrete wall comprising a series of woven textile unitsof sheet material having sections enclosing three sides of a square, theedges of the outer sections of one unit being connected to the edges ofthe intermediate sec tion of the next unit.

5. A framework comprising posts and a horizontal member spanning thedistance between the posts provided with a form of flexible, fibroussheet material to permit the pouring of the wall between the posts andbelow said horizontal member, said form comprising a pair of formportions each having outer face sheets and inner face sheets juxtaposedto each other, the inner and outer face sheets of the respective formportions being connected by tension sections of sheet material whereby awall may be poured with an outer covering of sheet material and with acentral web of sheet material.

6. A wall comprising a body of poured and set cementitious material,face sheet sections upon the outer faces of the cementitious materialcomprising a fabric of coarse mesh, tension sections of fabric of coarsemesh extending transversely of the wall between the face sheet sectionsupon opposite sides of the wall and being connected thereto, thecementitious material penetrating the interstices provided by the coarsemesh of the tension sections thereby providing integral connections ofthe poured concrete between bodies of concrete upon opposite sides of atension section.

'7. Wall form arrangement comprising a horizontal support and a form ofsheet material suspended from the support, said form comprising facesheet sections of fabric connected by fabric tension sections extendingbetween the face sheet sections, and ties secured to portions of theface sheet sections between their regions of connection to the tensionsections.

8. A form to receive poured concrete in the making of a concrete wall,comprising an assembly capable of being folded or rolled into a compactbundle and including opposite face sheet portions of woven textilefabric and tension sheets of woven textile material connecting saidportions, whereby the assembly may be suspended from a frame to afford acellular form.

9. A form construction comprising a form of' readily foldable, sheetmaterial providing opposite face sheet portions and tension elementsconnecting said portions, a horizontal support and connecting elementsholding the upper portions of the face sheet portions suspended from thesupport, a base, and means securing said portions to the base, so thatthe face sheet portions are under tension when receiving concrete pouredinto the upper part of the form, whereby the pressure of the pouredconcrete is primarily opposed by the tensile strength of said sheetportions.

10. Method of erecting a concrete wall upon a suitable base whichinvolves the employment of a fabric form having opposite spaced facesheet portions incapable of being self-supporting, comprising arranginga substantially horizontal support above the base, connecting the upperparts of the face sheet portions to the support so that concrete may bepoured into the top of the form, securing the lower edges of the facesheet portions to the base so that said portions are under ten- 9 sion,and pouring concrete into the top of the form to fill the space betweenthe face sheet portions.

11. Wall form arrangement comprising a horizontal support and a formsuspended from the support, said form comprising spaced generallyparallel face sheet portions formed of flexible sheet material, tensionelements connecting said portions, said support and form being arrangedso that cementitious material may be poured into the space between thesheet portions, said portions being suspended from the support in such amanner that the sheet material may bulge outwardly between said elementsso that its tensile strength may be primarily effective in oppos-' ingthe pressure of the cementitious material thus poured.

12. Wall form arrangement comprising a horizontal support and a formsuspended from the support, said form comprising spaced generallyparallel face sheet portions formed of flexible sheet material, tensionelements of similar sheet material connecting said portions, saidsupport and form being arranged so that cementitious material may bepoured into the space beween the sheet portions, said portions beingsuspended from the support in such a manner that the sheet material maybulge outwardly between said elements so that its tensile strength maybe primarily efiective in opposing the pressure of the cementitiousmaterial thus poured.

13. A structure of the class described comprising two walls extendingalong opposite sides of a space for cementitious material, at least oneof the walls comprising a horizontal series of portions which areoutwardly convex in cross section with intermediate troughs extendingvertically,

and partitions interconnecting the two walls at' said troughs to formvertical cells individual to said convex portions respectively.

ALBERT F. BEMIS.

